New course uses origami as one tool to teach students about space structures

Designing and building structures bound for space requires extreme engineering that considers the extreme pressure, temperature and other conditions they must endure. Undergraduate aerospace engineering students in The Grainger College of Engineering, University of Illinois Urbana-Champaign are required to take two courses on basic structural and material mechanics. Now students can choose to further their knowledge of advanced space structures in additional elective courses developed and taught by Xin Ning.

“In the required 300-level structures and material courses, students are taught the fundamental concepts of stress, strain, bending, torsion for simple structures like a beam or shaft,” Ning said. “In my new 400-level course, we discuss structural designs that are useful for rockets and satellites. The structural behavior of space structures is also unique. They are very sensitive to imperfections and subject to extreme space environments, for example. It’s specialized knowledge.”

Ning said structures courses in other engineering disciplines such as civil and mechanical don’t include the space-specific knowledge that aerospace engineers need.

The new course begins with a module on rocket structures that focuses on the behaviors of plates, cylindrical shells and spherical shells covering topics in deformations, buckling, and imperfection sensitivity.

“Those are the most basic structural designs in a launch vehicle. I hope this course can build a solid foundation for the next generation of rocket engineers,” Ning said.

Then Ning moves on to teach deployable satellite structures. In one lesson, Ning shows his students videos to build a connection between what they learn in class and real aerospace applications. One of the videos shows a space structure that is folded tightly to save volume onboard a spacecraft, but when deployed, can expand into a full-size satellite dish, for example.

During one week of the semester-long class Ning distributes paper for a lesson using origami.

“I think it's always nice for students to have a simple hands-on experience. Paper models enhance their learning. By folding the structures, they get a deeper understanding of the structure’s design,” Ning said. 

He teaches the students several other structural designs that can change shape in different ways. Those designs cover a wide range of deployable space structures from tape springs, composite booms and rod and plate mechanisms to inflatable habitats.

“The third part of the course is called ‘shake and bake,’” Ning said. “Satellites are introduced to a lot of vibration during launch, so ground testing includes shaking it. And then you need to bake it because in space the thermal condition is extreme.”

The homework assignments are designed to offer the students opportunities to master a variety of technical skills. The homework includes both theoretical analyses on the behavior of space structures and the use of ABAQUS, an industry-grade finite element software, to model those structures. The students are asked to compare the theory to software modeling to gain deeper understanding of the structural behavior. A homework assignment asks the students to make paper origami models and measure the folding and deployment motions.

In the spring semester, Ning will offer space structures II for the first time. It is purely a lab course.

“Students will design, do simulations, make and test representative space structures. It’s a more hands-on experience,” Ning said. “We’ll use 3D printers, other manufacturing equipment and our space environmental simulation facility next semester.”